A.1.8-2.0 B.1.5-2.0 C.2.0 D.1.8-2.5
A.0.5S B.1S C.2S D.3S
A.硫酸盐的硫 B.全硫 C.三氧化硫 D.硫酸钙
A.30 B.10 C.20 D.15
A.0.5L B.3L C.1L D.2L
